Most patients with ischemic cerebrovascular disease do not have problems with the intracranial blood vessels themselves, but are caused by embolism caused by emboli dislodged from outside the cerebral blood vessels, of which internal carotid artery stenosis and atherosclerotic plaque dislodged from the intracranial blood vessels account for about 60%. The incidence of cerebral ischemia in the population is about 0.3%. Recurrent episodes of loss of consciousness or focal neurological deficits that can be recovered within 24 hours are called Transient Ischemic Attack (TIA), which is an early manifestation of ischemic brain disease and will cause permanent neurological deficits sooner or later if they are not treated actively and effectively, therefore Ultrasound is a recognized screening test, CTA and MRA have the advantage of being non-invasive and can show the degree of obstruction in cross-sectional view, and most people still promote angiography as the gold standard for deciding whether to operate or not. A large number of clinical trials have demonstrated that carotid endarterectomy or endovascular stenting is effective in preventing stroke in both symptomatic and asymptomatic patients with carotid stenosis. In the United States, about 100,000 carotid endarterectomies are performed each year, but only a few hundred cases are performed in China, which is disproportionate to the number of people in China and should be taken seriously by the nation. Before and after surgery